Conveying mechanism for furnaces and the like



Aug. 29, 1933. MlLLAN ET AL 1,924.452

CONVEYING MECHANISM FOR FURNACES AND THE LIKE Filed Feb. 18, 1952 4 Sheets-Sheet 1 a M n MGM 5' W QZZWQ M W ATTORNEYS 29, 33- E. N. MILLAN ET'AL 1,924,452 v CONVEYING MECHANISM FOR FURNACES AND THE LIKE Filed Feb. 18, 1932 4 Sheets-Sheet 2 Z5 Z9 Z9 36 42 I O 0 o o 3o 34 O i ATTORNEY.

Aug. 29, 1933.

E. N. MILLAN ET AL CONVEYING MECHANISM FOR FURNACES AND THE LIKE Filed Feb. 18, 1932 4 Sheets-Sheet 3 o E m 0 (PM K O/ Z MYFM ATTORNEY.

Aug. 29, 1933. E, M|LLAN r AL 1,924,452

CONVEYING MECHANISM FOR FURNACES AND THE LIKE Filed Feb. 18, 1932 4 Sheets-Sheet 4 L Li; L LL LL}? LL ug L 72 if L 1N 74, e9 73 30 L ji Q i L 73 M BY Q Z ML M ATTORNEY Patented Aug. 29, 1933 CONVEYING MECHANISM FOR FUR AND THE LIKE.

ACES

Edward N. Millan and Percival o. cones, Middle town, Ohio, assignors to The American Rolling 7 Mill Company, Middletown, Ohio,

tion of Ohio a corpora- Application February 18, 1932. "Serial No. 593,816. v

. Our invention relates to mechanism adapted for the non-continuous conveying of materials or articles through a treating zone or device; and while our invention is not restricted to the specific embodiment hereinafter described, either asto exact construction or the manner or circumstances of its use; we will describe it for the purpose of making a disclosure, as applied to a heating furnace in which sheetsfor other articles are heat, treated preparatory to rolling or other working treatments. Such 'furnaces are usually of tunnel-like construction, having an entrance at or near one end, and an exit at or nearthe other, and they areequipped with some sort of ccnveying'mechnism designed to cause sheets, or other articles, to, pass through them to be heat treated and to be deliveredat the far end, preferably under controlled conditions of temperature and time. of delivery. i.

It is an object of our invention to provide an improved conveyor mechanism for carrying materials or articles through a treatment zone,

As applied tov furnaces, it, is an 'objectof our invention to secure better heat distribution in the furnace and a more uniform heating of the articles being treated, such as packs, bars. sheets and the like. i "It is an object of our invention to prevent undue loss of heat carried out of the furnace by conveyorcmechanisms.,.

It is, also our object to provide means fordelivering sheets, or the like, Without cold spots. i r I it is still-another object of our invention to. provide conveying mechanism which is adequate to the ends hereinabove mentioned, and which at the same time is adapted for the movement of sheets, to such articles.

More specifically it is an object of. our invention to provide in connection with conveying" means, supporting means within the furnace, permitting both the even heating of the pieces and r sarily been removed from the furnace in themes... y of anarticle. Another specific objectis to secure these functions andadvane tages a structure which. 'neverthelessis capable of rapid removal of pieces from the furnacev speed with which the furnace may" be filled with or emptied of pieces to be heatfltreated These and other objects of our. invention" which will be set forth hereinafter or will be.

clcs, or the like, without detriment oi the conveyor portions which our specifications, We accomplish by that certain construction and arrangement of parts of which we shall now"describe the-aforesaidgex emplaryeznbodiment, it being understood that our invention; is not restricted thereto, nor to the hereinafter described circumstances of use, but

is capable of other uses'and maybe modified by those skilled in the art without departing.

from thespirit thereof. Reference is now made Figure :1 is a longitudinal vertical section tothe drawings, wherein: 1

Figure 4 isa plan view of said drive.

Figure dis a spread out diagram of the connections. t i a Figure '6 is acamtype limit switch geared-to sprocket similar to 4., exception the front end of the furnace (not shown in; Fig. 1),-prop'erly timed through "suitable gear reduction.

Figure '7 is a cam type limit switch mounted on the shaft of the reducer 31'. I 1 Briefly, in the practice of four inventionfwe provide a conveying mechanism, in the furnace, capable of continuous controlled movement and we likewise provide, within the furnace means for liftinglthesheets or articles .from the conveyor, whereby the conveyor-maybe reversed and the heated portion thereof brought-back into the'furnace as desired. The-means for lifting the sheets or articles from the conveyor comprise means, affording a satisfactory support for cold spots due to a conveyor 'mechari'ism which is not at furnace temperature. In the particular type 'ofafurnace shown a chain conveyor is provided, the chainportion of which in the up-,

per or forward traveling part is preferablyflo catedwithin or beneath the floor of the furnace,

there being provided conveyor arms or fingers". Y

which extend through saidfloor. Driving means for thisconveyor' will be located outside the furnace, as will likewise, be driving means. for the. lifting devices;, the "operating meansfforsaid lifting, devices being preferably located beneath the floor of "the f urnacei Since'ourlifting deapparent to one skilled intheart 'upon reading vices move vertically thrcughthe furnace floor;

pieces are then raised by the lifting devic'esfrom the conveyor. A cyclical operation'ofthis sort is contemplated and is maintained as will hereinafter be more fully described; but the cycle has nothing to do with the length of movement of a the conveyor proper, and consequently our furnace may be filled or emptied as rapidly as may be desired. a

'In Fig. 1 we have showna furnace indicated generally at 1, having a floor 2. The portions of this furnace have been shown'diagrammatically since they will be well understood by those skilled in the art and do not need special disclosure. A conveyor has been indicated diagrammatically in Fig. 1 at 3. One of the end sprockets for this conveyor has'been indicated diagrammatically at 4; and at 5 there has been indicated a feeding table adapted to deliver sheets, -packs, bars, or other articles, to theconveyor. aforesaid. v

In Fig. 2 it will beseen that the conveyor comprises chain 'members 6, preferably located as shown within the floor of the furnace- These chain members may be provided with anti-friction devices such as rollers? operating in channel iron tracks 8'Wll7hill the furnace floor, and the various links of the conveyor chain will be provided with upstanding conveyor arms or fingers 9. These extend through slots 10in the furnace floor, and in order to be able to withstand the heat of the furnace they will preferably be made of some heat resisting alloy, as is Well known in thisart; The conveyor returns beneath the furnace as shown at 11, where the links ride in suitable brackets 12 fastened upon supports 13. The sprockets of the conveyor,

usually one at each end of the furnace, will be arranged with a suitable power drive such as an electric motor.

Beneath the furnace floor (which as shown in Fig. 1 is supported upon suitable beams 14, or

' the like), we provide a beam or bar 15, which is mounted for vertical reciprocation upon pins or rollers 16,,riding in supporting members 17, having yokes 18. As many of the bars 15 will be provided asmay be found necessary. The bars 1 preferably extend longitudinally of the furnace,

and preferably also are interconnected by cross beams 19, forming therewith a framework.

Upon this framework we mount vertically extending arms 20. These arms pass through holes 21 in the furnace floor, but since they'can move only vertically, these holes need be very little larger than the arms themselves, and they may additionally be closed by washer members 22, either fixed on the arms or slidable with reference thereto. This washer and the arms themselves will preferably be made of heat resisting alloy. The arms may bear at their upper ends common supporting bars 23 extending longi' tudinally of the furnace and adapted to support supporting lines between which the conveyor chain arms 9 may travel. Obviously as many of the arms and supporting members within the furnace may be employed as are found necessary to provide the requisite support. 7

The bars 23 form supporting means for sheets or articles, adapted either to hold them station:

ary above the conveyor, or to lower them into position for movement by the conveyor. The vertical reciprocation of the arms 20 is determined by the beams 15, which are guided for We have found it very satisfactory to provide a series of bell cranks, pivoted to suitable pivot members 24 upon a foundation or other support; One arm 25 of these bell cranks is connected by a linkage member 26 to the beam 15 at a pivot member 27. The other arm 23 may be pivoted to aconnecting rod ,orrods 29. Movement of this connecting rod, tending to cause the bell cranks'to turn in a clockwise direction, will raise the beams 15 and the supporting members Within the furnace.

To the end of effecting controlled movement of the bell cranks, we providea source of power such as an electric motor 30 or the like, which, through an appropriate gear reduction mechanism 31, where necessary,may-be caused to transmit'power to a main shaft 32. This shaft may be mounted in bearings 33 on the foundation; and we prefer to mount a lever 34 on the shaft,

and to connect this lever by a linkage member 35 to'a' lever '36 on the drive shaft of the speed reducer 31. The length of the levers is so proportioned that when the shaft of the speed reducer rotates through a complete turn, the shaft 32 will be rocked and returned through the desired arc forthe actuation of the beams 15. Leverarms 37, non-rotatably mounted upon the main shaft '32, are operatively connected to the connecting rod 29. The levers 3'7 may,

if desired, be part of bell cranks having addi.

tional lever arms 38'connected to the beams 15 by linkages 39.

Since the weight of the frame and supporting members forming the assembly attached to the beams 15 is considerable, we prefer to counterweight it by means of weights flO on' cables 41.

The cables pass over sheaves {i2 and are connected to the lever arms 34 or other suitable lies theconveyor 3, it is convenient to mount it, or a portion of it at least, uponthe beams 15, so that a' reverse movement of the conveyor will not drag the delivered sheet or article back toward" the furnace. r

' The operation of j our.v device is as follows: Assuming that the furn'ace is full of pieces, and

that the supporting members 23 are holding thesepieces away from contact with the conveyor, the motor 30 is first started. When started the. driving mechanism will be in the position shown in Fig. 3. The shaft 32 will be rocked in a counterclockwise direction, the lever 36 passing through a half revolution for the purpose. This drops the framework and sup port assembly attached to beams 15, lowering the pieces or articles onto the conveyor arms 9.-

of power connected with the -conveyor 3 will be started drivingfthe conveyor in the forward positioned the conveyor is again stopped. The

direction through a desired distance, which will usually be at least sufiicient to deliver a piece :from the furnace, but may be as much longer as desired. At thesame time, another piece -may befed onto the conveyor 3 from the feeding table 5, and carriedinto the furnace.

When a piecehas been-delivered fromthe furnace the conveyor3 will of course be stopped.

If this operation has resulted incarrying the next piece in line out of the heating zone, the next operation may be the reversal of conveyor 3 for a predetermined length of travel. When the pieces remaining in the furnace are, properly motor 30 is next started, and is allowed to run until lever 36 hasreturned to the 'positio'r'1"shown in Fig. 3. This raises the supports, 23, lifting the pieces from'the conveyor. The motor,30 is then stopped. @A'fterward. conveyor 3. may be run .in the reverse directionsufiiciently to return to the furnace the heated .portionof the I conveyor elements. The cycle] is repeated for each piece or series of pieces to be delivered into or out of the f'urnace;f but thej cycle does not limit the length of travel of the conveyor 3; and the furnace may be entirely filled or entirely emptied atone operation; {Or in any one 'operation as fmanvpieces as, desired" may be serially cycle.

fIt will" be clear other primemover attached to cOnveyorB. A

stopping button may bejprovided, to initiate operations asfollows: the stopping of conveyor 3'; the starting of motor 30 whereby the pieces are-againlifted from the conveyor; the stopping for motor 30 and'if'desireithe reversing of conveyor 3 and the stoppage thereof after a predetermined travel.

controls may be provided forlthe conveyor. 'If

a preliminary reversingeof the conveyor is de'- y siredprior'to the removal of the pieces therefrom; this may, by appropriate limit switches;

be'provided'as an automatic part of the cycle.

In this waythe operations of the lifting and" supporting elements of our furnace may be so arranged, with respect to the control of theconveyor that themanual operationthereof by afs'eri es of control buttons, or theflik'e, will be as simple as the operationof a furnace having nothing but the chain conveyorh Under some. circumstances the full automatic operation of theffurnace maybe desired," or some type of semi automatic operation'in which the move ments of' the articles through'the 'furn'aceare determined by some specific conditionorfcon dition's. .Thus the cycle of operations may bestarted by a time clock to operate a starting that by means of appropriate, relays and limitswitches the operations .of mo tor 30 may be caused to have a fixed relationship to the operations of the conveyor 3. -a'. starting button may beprovided which will ini-G' .tiate automatic operations as follows: the starting of motor so as tolower the pieces" onto thec'onveyor; the stopping of motor 30 when this is done; and "the starting of the motor or Or separate I reversing,

tion, to the movements of the lifting and, sup-- porting'devices, even though the lifting and lowering of pieces 'within the furnace ,may be rendered automatic with respect to starting,. stop.-

ping, or reversing operations of the, conveyor.- Where the :furnace isto be employed for the heating, of sheets or packs for hot rollinaand 7 where the length of these sheets or packs may vary,";it is convenient to have the, cyclesgof operation (whether started by handior by time clock) determined by the length "of the piece or pack-passing. throughthe furnace; 5A1 furg The switch ,50 is:closed only arms" 20j, are in1up position. The switch-51 is ;closed as soonlas, there is, an appreciable downward movementof the arms 20 andjremainsclos'ed position andremains closed until the arms/20 reach bottom position; The switch 53 closes and opensagain justbefore the arms 20"reach* the, top, position. The switch 54 closes just be: ."fore the arms '20 reach the bottom position and opens when the arms .20 have reached'the bottom position. The switch 55 closes and opens again when there is, an appreciable upward 'movement, of the arms 20. .The switches; 56, 57and 58 areclosed when'ithe furnacel is fully delivered from the furnace in onetravelflof the'conveyor 3, and are open in. the

starting 1 position, ,The switch ,61 closes when the'pack hits the -trigg'er, 44. The switch 62 is connected to the trigger 44msuch a. way that the: switch 62, 62' is closedwhen the-packhits the g'trig er, 2 and. the switch 62, 62 is closed 1 when the trigger is not-in contact with the pack. Latching-relays are indicated by the numerals 63 and'64. 1 Theswitch 65 is a control switch-for the non-automatic operation of the *conveyory3 for .filling the furnace with packs when: starting operation and the like. ,The numerals .65'p'and 65 indicate the forward" and reverse 1 position of; the switch 65. "The selector switch for .au,-

The switch- 68, if desired,"maybe usedinplace 1 ofitheifoot switch 67. The switch 68 is-actuated by a circuit ,whichis controlled bya'clock in order that agpack may bedelivered from'th e furnace to ,theimill automatically, at chosen and constant intervals. The switch '69 is a- 60111130? tor switch" in thejcircuit of,the motor; 36;: A

661 and magnetic coil 69', when energized; closesythe switch; 69.1,,The: switch 69 isaetuatedby the magnetic coil 69. 'Ihis switchjisIopen when in the'switoh 69- is;open, and closedjwhen the switch 69 is closed The switch 70 is a forward 1 contactor switch in the circuit. of;the motor 7 8,-

The switch 71 is' a reversecontactor switch in the circuit, of the imotor '78. The magnetic coils 70' and 71","if energized, close the switche 70 and 71 respectively. Th'e'swit'ches 7.0 and 71fbear the same relation' to-the "switrihes-"m andi'71,i respectively, as theswitfch 69"!- iioes to U 'the switch An overload coil'gof overload r-j lay 72 "is in; circuitriwith the motor'--"78;-

until the, arms 1 20 reach top position. The -:9

switch 52 iszclosed when the,.arms 20 arein up tion.

overload coil of overload relay 73"is in circuit with the motor 30. The numeral 74 represents an emergency stop button, and there is asafety switch 75 in the circuit of the motor '78 and a safety switch '76 in the circuit ofthe motor 30. The power supply is generally indicated by" the numeral 77. A'motor 78 drives the chain conveyor 3.

The sequence of operation is as follows: A controller 01' clock closes the" switches 67 or '68 I as desired. The coil 69' -'-is energized through switch 70 and the switch 70". The chain conin a clockwise direction; The switches .56, 57

7 although the switch 54,

veyor 3 moves in a forward 1 direction. The

closing of the switch 54 also energizes the coil 64 ofthe latching relay switch 64. This estab lishes a holding circuit for the coil '70, and, opens again the coil 70f remains energized. Y

The pack hitting the trigger 44 closes the switches 61 and 62'62. lishes a parallel holding circuit'for the coil .70 and also energizes the unlatching coil 64" of the relay 64. The contacts of the relay- 64 open. The switch 62-62 energizes the coil, 63"

of the latching relay 63, but at this time does not establish a circuit, since the switch 62 '62 is open. The cam typelimit-switch '(Fig'. 6) which is geared to the conveyor sprocket shaft on the front end of-the furnace begins to turn and 158 open first, then the switches 59 and-60 close. As the rear endof the pack clears the trigger 44, theswitches 6,1 and; 6'2'62 open. The coil is deenergize'd and the 'contactor 70 and the switch '70" open. The chain" conveyor 3 stops. The switch 6262" "is now closed, which energizes the coil 69 through the contacts of the relay 63. The contactor 69 and theswitch 69" close. The arms 20 move upwardly. The cam'type limit switch (Fig; '7)

moves in a clockwise direction. The first-switch 55 closes" and then opnsg'agaimtherebyenergizing the unlatchin'g coil 63" of the relay 63. The relay 63 opens, but the coil 69'remains jen ergizedthrough the switches 51 and 59; Asthe arms 20' approachthe top position, the switch 50 closes, then the switch 52 closes, and finally at the end position the switch- 51 opens. The

coil 69' is deene rgized and'the contactor=69 and the switch 69' is open. The; motor 30 then stops,'and the arms 20 are stopped in their top' position. 7 Just before reaching the'top position,

the switch'53 closes and then opens'againl This energizes the coil '71 and the 'contact or '71 and the switch 71 closes. Thus, the chain" con veyor 3 moves in a reverse direction. The cam' type "limit switch (Fig. 6) ;.moves in a counter clockwise direction and the switches 59 and '60 open. The'switch 60 deenergizes' the coil 71 and the contactor 71 and the switch 71f o ens,

' thereby stopping the'motor '78. The switches 56, 57 and 58 close again, completing the cycle. Upon closing [of' the foot switch 67 or the timed The switch 61 estab-" contact 68, the above described cycle or pe aQ 7 tion'will be repeated.

-Having'thus described our invention, what we claim as'new and ent,-'i's:

- 1.- In a furnace or jotherzone treating device, a- 'chain conveyor mechanism having laterally desire to secure by Letter Patspaced, longitudinal, flexible elementsprovided with work carrying fingers, vertically reciproca-. ble'rail' elements positioned in the interspa'ces between said spaced elements, supporting means attached below said rail elements, said rail elements being adapted toraise articles from said fingers and to lower articles thereon, said supe porting elements adapted to be lowered into said interspaces so as to bring said rail's below the tops ofsaid fingers.

2. In a furnace, or the like, a" conveyor comprising a plurality of laterally spaced, longitudinal,1fiexib1e elements provided with work carrying lfingers, vertically reciprocable rail elements between said spaced elements,'supporting means attached below 'said rail"elements, said rail elements being'arrangedto be lowered between said spaced elements to below thetop of of said'fingers, or to be raised above the top of said fingers, anddrivingmeans for said reciprocating railelements. Y

l 3. In afiirnaca or the like, a conveyor comprisinga plurality of laterallyspaced,1ongitu-.

dinal, fl exiblejeleinents, vertically reciprocable rail elements located in the i'nterspaces between said spaced-elements, a frame below said rail elementsand to which saidrail elements are attached, means for guiding thevertical reciplocation of said 'framefand means for causing said frame to'move' vertically." 4.'In1a.furnace, or the like, a conveyor comprisinga plurality of laterally spaced, longitudinal, flexible 'elements,'vertically reciprocable rail elements located inthe interspacesbetween I said spacedrelements, a frame below said rail elements and to which said 'railelements areat; tached, means for guiding the vertical recipro cation of said frame, .and means for causing said a source of power and an operative connection frame to'move vertically, said means comprising i;

between the same and said 'frame,a sourcefof" powerffor said conveyor and electrical'control means forj interrelating the movements "of: said conveyor and said. rail elements.

I 5. In combination with a furnace having 'a noon-chain conveyor elements having 'sub'stantially parallel upper laps disposedbelow theup-f conveyor elementsa frame to which said members are attached, said. framebeing' below said floor-and said-members extending through said floor, means for vertically reciprocating lsaid.

frame, rails attached tosaid members, said, r 11s w extending in the direction of said conveyorele: ments, a-source of power motion transmitting means for lifting said frame, vertical guiding means for said frame, and an operative connection between said source of power and said ;mo

'tion transmitting means, a source 'of power for said conveyor and control means for. effecting the sequential. operation of said severallpower sources. EDWARD N. MILLAN.

*PEROIVAL C. JONES.

, V V 130 .per surface of said floorand having supporting. i elements extending above said suriace, vertical v} t 1y reciprocating members located: between .said 

